Acne is a common skin condition that affects many individuals, particularly during adolescence. It is characterized by the presence of pimples, blackheads, whiteheads, and often, inflammation. While there are several factors that contribute to the development of acne, the primary cause is the overproduction of sebum in the sebaceous glands of the skin. This excess sebum, along with dead skin cells and bacteria, clogs the hair follicles, leading to the formation of acne lesions. Among the options provided, the correct answer is option 'A' - Staphylococcus.

Staphylococcus and Acne Formation:
-----------------------------------
Staphylococcus is a genus of bacteria that includes several species, such as Staphylococcus epidermidis and Staphylococcus aureus. These bacteria are naturally present on the skin surface. While they do not typically cause any harm, certain strains of Staphylococcus, particularly Staphylococcus aureus, can contribute to the development of acne. Here's how:

1. Inflammation and Immune Response:
- When the hair follicles become clogged with excess sebum and dead skin cells, it creates an ideal environment for bacteria to thrive.
- Staphylococcus bacteria, including Staphylococcus aureus, can colonize these clogged follicles.
- The presence of bacteria triggers an immune response, leading to inflammation.

2. Inflammatory Acne Lesions:
- The immune response causes an influx of white blood cells to the affected area, leading to the formation of inflammatory acne lesions, such as papules, pustules, and nodules.
- These lesions are characterized by redness, swelling, and tenderness.

3. Role of Staphylococcus aureus:
- Staphylococcus aureus produces enzymes that can break down the sebum, releasing fatty acids.
- These fatty acids further contribute to inflammation and the development of acne lesions.

It's important to note that while Staphylococcus can contribute to acne formation, it is not the sole cause of acne. Other factors, such as hormonal changes, genetics, and lifestyle choices, also play a significant role. Therefore, treating acne involves a multifaceted approach, including proper skincare, maintaining good hygiene, and in some cases, medical interventions like topical or oral medications.